Religious factionalism threatens our ability to work for the common good.

I recently had a conversation with a leading MP, a friend of the Jewish community and the state of Israel. This individual has gone to great lengths to protect the UK-Israel connection. In the course of that conversation, he told me that the level of anti-Israel rhetoric is rising rapidly and that much of this hyperbolic criticism of Israel is alarming and often hateful.

Then he asked me a question that struck straight in my heart: "With all the problems that face Israel today, why can't the Jewish community unite and establish a common front? Jewish unity can help divert the threat that exists against your own interests. And why is it that when solidarity is needed more than ever, Orthodox rabbis are more likely to attend an interfaith event at a church or a mosque than to step foot in a non-Orthodox synagogue? That seems incomprehensible to an outsider!"

He is right: it is incomprehensible and our disunity should be incomprehensible and unacceptable to any Jew as well. We are creating sects among us in which Jews only associate with Jews who do not associate with other Jews. And more than being incomprehensible, a grotesque factionalism created by our own choices, threatens the very existence of the Jewish people because it has divided us into "machanayim" or "separate camps".

This self-imposed segregation inevitably leads to sinat chinam (needless hatred of one Jew for the other) and denies us from realising one of Judaism's primary mitzvot, ahavat Yisrael (the love of each Jew for the other). Sadly, so much of the way we talk about each other is filled with imprecations, vilifications, insinuations and character assassinations. Our separation from each other reflects insecurity, not strength, in what we believe and how we practise our Judaism.

In many ways, we Jews have become idolatrous, in that absolute denominationalism has taken hold of our organisational and spiritual being. A good definition of idolatry is a worship of the part as if it were the whole - that is us. To overcome idolatry, we must begin to make all the parts of our Jewish community inseparable units of the common Jewish good. Achieving that goal will require courage, the wisdom of Judaism and a sincere love of the Jewish people.

Increasing and strident denominationalism is not just coming from the Orthodox communities. Progressive Jews and Judaism, I have discovered since being in London for a year now, also take stereotypical attitudes toward our Orthodox brothers and sisters that are simply false and bigoted. Orthodox rabbis will not set foot in a Reform, Liberal or Masorti synagogue, while the non-Orthodox do not feel comfortable in a United synagogue; the Progressives cannot unite among themselves, while the Charedim will not recognise mainstream Orthodox Judaism.

When will this madness end? When will Jews realise that we need all parts of the community and that we need each other to be truly successful to ensure Jewish survival for the next generation? We should be praising the accomplishments of each movement: Reform, Liberal, Orthodox, Masorti and independent rather than revelling in our segregation from each other.

We Jews have a history of debate and disagreement regarding the correct path for Judaism, a debate which has often nourished the development of Judaism: the rabbis struggled against Gnosticism, the house of Shammai argued against the house of Hillel, Pharisees blasted the Essenes and Sadducees, Samuel battled against those who pleaded for a King, the kabbalists burned the books of Maimonides, Rabbi Saadia Gaon polemicised against the Karaites, the Mitnagdim declared a cherem (excommunication) against the Chasidim, the Orthodox and the Reform fought tough ideological battles in Germany over the nature of emancipation and Enlightenment, the Eastern Europeans and the Zionists were ostracised by Western European Jews, and so forth.

But those historical divisions are not recipes and excuses for our current state of affairs. Passionate ideological disagreements are normal in the course of historical evolution, but sinat chinam can turn "arguments for the sake of Heaven" into intolerance and self-destruction.

I would like to see the next Chief Rabbi reach out to the entire Jewish community and to demonstrate once and for all the importance of ahavat Yisrael, for the enemy has been misplaced: the real threat is not each other, but instead comes from antisemitism and from those who vow to see the state of Israel be extinguished.

Internally, the threat to our very survival comes not from Orthodoxy or non-Orthodoxy, but from Jewish illiteracy, apathy and assimilation. It also comes from a strident ultra-Orthodoxy that is now verbally assaulting nine-year old girls on their way to school. That seething hatred of the other comes from a view that sees the right only in the self and none at all in our fellow Jew.

There is a benediction for pluralism that can be found in the Talmud, tractate Berachot, that says: "Blessed is he who is wise of all secrets and who knows that the opinions of each is not like that of the other just as the face of one is not like the face of the other."

The opportunity has arrived for the Jews of the UK and everywhere else, to seek a different way from the ideological segregation that divides us so painfully. We have incredible potential to be visionaries and leaders in seeking a new path that will ensure the worthy goal of Jewish survival for our children and children's children.

Let us recite the Shema together. Let oneness among us mean something when we pray, because then we will truly understand the oneness of God.